Influence of ethanol, water, and their mixtures as co-solvents of the supercritical carbon dioxide in the extraction of phenolics from purple corn cob (Zea mays L.)

Autor(es)

Monroy, Yaneth M. ; Rodrigues, Rodney A. F. ; Sartoratto, Adilson ; Cabral, Fernando A.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF SUPERCRITICAL FLUIDS; v. 118, p. 11-18, DEC 2016.
• Citações Web of Science: 19

Resumo

Supercritical carbon dioxide (scCO(2)), ethanol (EtOH), and water are considered GRAS (Generally Recognized as Safe) solvents. They exhibit considerable advantages in the extraction of phenolic compounds with a wide range of polarities, such as the anthocyanins found in purple corn (Zea mays L.). To evaluate the effect of ethanol and water as co-solvents in the scCO(2) extraction of phenolic compounds of purple corn cobs, extracts were obtained at 400 bar and 50 degrees C using EtOH (CE), water (CW), and mixtures of EtOH/water 50% (CE50), and EtOH/water 70% (CE70) as co-solvents of scCO(2). The overall yield (X-0), the extraction yield of total monomeric anthocyanins (TMA), total phenolics (TP), total flavonoids (TF) were determined in the extracts, as well as the antioxidant activity (AA) expressed as EC50/DPPH, color, and presence of specific anthocyanins by HPLC. The lowest extraction yield (4.15%) was obtained when ethanol was used as co-solvent (CE), and the highest yield (24.4%) was observed when using a mixture of EtOH/water (70%, CE70) as co-solvent. The presence of EtOH and water was essential to obtain concentrated phenolic extracts, with values around 66 mg cyanidin-3-glycoside equivalent per gram of dried extract, 290 mg gallic acid equivalent per gram, and 117 mg catechin equivalent per gram, and antioxidant activity of CE50 =31 mu g/mL by DPPH. (C) 2016 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 12/51317-1 - Desenvolvimento de produtos e processos por tecnologia supercrítica: construção de uma unidade multipropósito para obtenção de extratos de interesse industrial
• Beneficiário: Fernando Antonio Cabral
• Modalidade de apoio: Auxílio à Pesquisa - Regular